<!doctype html>
<html lang="en">

<head>
  <!-- Required meta tags -->
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">

  <!-- Bootstrap CSS -->
  <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.1/dist/css/bootstrap.min.css" rel="stylesheet"
    integrity="sha384-F3w7mX95PdgyTmZZMECAngseQB83DfGTowi0iMjiWaeVhAn4FJkqJByhZMI3AhiU" crossorigin="anonymous">

  <title>Bootstrap练习</title>
  <style>
    #bs div {
      border: 1px double red;
      /* margin: 1em; */
      padding: 1em;
    }

  </style>
</head>

<body>
  <div class="container">
    <h1>Hello, world!</h1>
  </div>
  <div class="container" id="bs">
    <div class="row">
      <div class="col">
        1 of 2
      </div>
      <div class="col">
        2 of 2
      </div>
    </div>
    <div class="row">
      <div class="col">
        1 of 3
      </div>
      <div class="col">
        2 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
      <div class="col">
        1 of 3
      </div>
      <div class="col">
        2 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
      <div class="col">
        3 of 3
      </div>
    </div>
    <div class="row gx-5">
      <div class="col-4">1</div>
      <div class="col-4">2</div>
      <div class="col-4">3</div>
    </div>
  </div>
  <div class="container px-4">
    <div class="row gx-5">
      <div class="col">
        <div class="p-3 border bg-light">Custom column padding</div>
      </div>
      <div class="col">
        <div class="p-3 border bg-light">Custom column padding</div>
      </div>
    </div>
  </div>
  <!-- Optional JavaScript; choose one of the two! -->

  <!-- Option 1: Bootstrap Bundle with Popper -->
  <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.1.1/dist/js/bootstrap.bundle.min.js"
    integrity="sha384-/bQdsTh/da6pkI1MST/rWKFNjaCP5gBSY4sEBT38Q/9RBh9AH40zEOg7Hlq2THRZ"
    crossorigin="anonymous"></script>

  <!-- Option 2: Separate Popper and Bootstrap JS -->
  <!--
    <script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.9.3/dist/umd/popper.min.js" integrity="sha384-W8fXfP3gkOKtndU4JGtKDvXbO53Wy8SZCQHczT5FMiiqmQfUpWbYdTil/SxwZgAN" crossorigin="anonymous"></script>
    <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.1.1/dist/js/bootstrap.min.js" integrity="sha384-skAcpIdS7UcVUC05LJ9Dxay8AXcDYfBJqt1CJ85S/CFujBsIzCIv+l9liuYLaMQ/" crossorigin="anonymous"></script>
    -->
</body>

</html>
